Crucible mouthpiece for type casting machines



. March 14, 1939. 2,150,339

CRUCIBLE MOUTHPIECE PoR TYPE CASTING MACHINES s. RABlNowlTz Filed Aug. 1l, 1937 www lNvEN'roR RAB/N0 A QRNEY SEYMOUR Patented Mar. 14, 1939` PATENT DFFICE CRUCIBLE MOUTHPIECE FOR TYPE CASTING MACHINES v Seymour Rabinowitz, New York, N. Y. Application August 11, 1937, serial No. 158,463

1 Claim.

This invention relates to molds for casting type and relates more particularly to means for evacuating theair from the mold in advance ofthe oncoming molten type metal.

i In Linotype, Intertype, and other type casting machines, molten type metal is forced into a mold cavity formed by a mouthpiece, upper and lower mold members, and a line of matrices. Present structures depend upon the oncoming molten metal to force the air contained therein from the mold cavity. 'I'his ineicient method of evacuating the air frequently results in the cast type being formed with pockets and blow-holes formed by air trapped in the mold. It is apparent, therefore, that the type is poorly formed,ofiering little resistance to fracture and mutilation under ordinary printing pressure. The type is often formed, especially in the larger sizesfrom 36 point upward, with imperfect faces and therefore require special` polishing or burnishing operations to make them suitable for use.

The present invention, in order to obviate the above-mentioned faults, seeks to provide means to afford ready egress of the air from the mold, and further contemplates evacuating said air so the oncoming molten metal may more easily fill the mold cavity and, therefore, provide wellforrned cast type free of imperfections such as blow-holes and the like.

It is, therefore, anobject of the invention to provide a mouthpiece having passage means in communication with the mold cavity for affording egress of the air from said cavity under the urgency of the oncoming molten metal.

Another object of the invention is to pro-vide means for drawing the air from the cavity, utilizing the mentioned passage means, so the oncoming molten metal does not actually displace the.

air in the mold cavity but enters a cavity from which most of the air has been already withdrawn. v

In employing the invention some of the molten metal may be inadvertently drawn from the mold cavity through the mentioned passage means'. Another object, therefore, is to provide means for collecting said metal so that the suction means employed for evacuating air from the cavity may not be impaired thereby.

With the above and many other objects, features, and advantages in mind, the invention is embodied, in its present preferred form, in the accompanying drawing which is described 'in detail in the following specification.

In the drawingzq Fig. 1 is a cross-sectional view of a type casting YCrucible and mold embodying features of the invention.

Fig. 2 is a front View of the mouthpiece and showing the means for applying suction to the mold cavity. K

Fig. 3 is an enlarged broken sectional view showing details of the mold cavity.

As seen in Figure l, the metal pot Crucible 5 is provided with a pump plunger S, movable reciprocatorily in the well l' as by means of the plunger rod 8. By these means the molten metal M may be forced upwardly into the throat or spout 9 which opens into the mold cavity I0.

'Il-he cavity Il is. usually formed by a mouthpiece I i, an upper and a lower mold member respectively I2 andl, and a line of matrices I4. The mouthpiece is provided with a dovetail slot I5 for engagement with a complementary portion I6 on` the spout 9.

In its present form, the mouthpiece is provided with a stepV I'I to form af relatively thick upper portion. I8 and a thinner lower portion I9. The thicker upper portion is provided with a plurality of holes 2) entering on the cavity I0 and communicating with the spout 9 through the medium of a common connecting recess 2| in the back of the. mouthpiece.

From the foregoing, it may be seen that molten metal forced upwardly in the spout 9 by the plunger 6, will enter the recess 2l, pass through the holes 2B, and fill the cavity Il) to form the type slug therein.

It will be noted that the lower mold member I3 is formed with a rearwardly directed lip 22 which is spaced below the step II to form a passage 23 between the lower mold member and the mouthpiece, and communicating with said passage and between the holes 20 there is preferably provided a plurality of notches 24 which are also open to the mold cavity IU. Thus, as metal is forced into the mold cavity, theair therein is displaced through the notches 24 into the passage 23.

If desired, the improved arrangement may be used as above described and will present distinct advantages over prior structures. However, the present invention contemplates actually withdrawing the air from the die cavity in advance of the oncoming molten metal and for this purpose the mouthpiece is formed at 25 with a series of passages communicating the passage 23 with a passage 2G formed in a block 21 positioned against the lower edge of the mouthpiece II. Y

The passage 2G is entirely closed to form a.

tube 29 in communication with the lower porition of a metal and air separator 30, theY top Eof which is connected kas by means of the pipe.

3|, to an air suction device 32 of usual 'design In operation, the level of the molten metal in the crucible and in the spout is approximately that shown in Fig. l and hence the suction applied to the cavity I D by the suction device 32, will not draw the metal up into said cavity. When the plunger 6 is depressed, however, the molten metal is raised in the spout, and enters the die cavity quite freely and with little resistance because of the air rarefication caused by the suction device. Thus the slug formed in said cavtiy will be free of blow-holes and pockets, have perfect type faces, and will have a solid mass capable of withstanding hard usage.

Should some of the molten metal be withdrawn with the air through the line29, the separator will collect such metal to obviate its reaching the suction device which might be impaired thereby.

The foregoing, it is believed, presents several distinct improvements over prior structure of this type and it is apparent that the details of construction may be immaterially changed by skilled persons seeking to practise the invention. The prior pertinent art, rather than the instant disclosure, therefore, should form the basis of interpretation of the spirit and scope of the invention as claimed.

I claim:

In type casting apparatus, aV crucible mouthpiece, mold members associated with said mouthpiece to form a mold cavity, said mouthpiece having a plurality of holes for passing molten metal to said cavity, a plurality of notches formed in said mouthpiece, said notches and saidholes being alternately arranged and said notches communicating with said cavity for receiving air from said cavity displaced by oncoming molten metal, said mouthpiece and one of said mold members being arranged to provide a passage having communication with said notches for receiving air therefrom, said passage being adapted to be exhausted of air and thereby exhausting the cavity of air.

SEYMOUR RABINOWITZ. 

